Evaluation of the timing of initiating continuous renal replacement therapy in community-acquired septic patients with acute kidney injury

Acute kidney injury (AKI) in community-acquired septic patients is often associated with relatively high mortality rate. However, the appropriate timing for continuous renal replacement therapy (CRRT) initiation remains controversial. In the present study, we retrospectively analyzed 123 community-acquired septic patients with AKI admitted to the medical intensive care unit (ICU). The baseline patient characteristics and renal function parameters were compared between survivors and non-survivors. Then, we used the Cox proportional hazard analysis to identify the risk factors for ICU mortality. Moreover, we employed the area under the receiver operating characteristic curve analysis to determine the cutoff time for CRRT initiation. Finally, we used the cutoff time to separate the patients into early (treatment initiated earlier than the cutoff time) and late (treatment initiated later than the cutoff time) CRRT groups and performed the Kaplan-Meier survival analysis to assess the overall mortalities. At the time of ICU release, the mortality rate of the 123 patients was 48.8% (n = 60). We identified several baseline characteristics and renal function parameters that were significantly different between the survivors and the non-survivors. All of them were also identified as the risk factors for community-acquired sepsis. Importantly, the cutoff time point to distinguish the early and late CRRT initiation groups was determined to be 16 h after AKI onset. Based on such grouping, the mortality rate was significantly lower in the early CRRT initiation group at 30, 60 and 90 days. Our data suggest that initiating CRRT within 16 h may help improve the mortality rate of community-acquired septic patients.